Do you know how much sugar your kids eat?

One of my favorite shorthand ways of telling people how to eat is, “If it comes in a bag or a box, don’t eat it.”

That’s an oversimplification, of course. Some healthy foods, like eggs, do come in boxes—or cartons, at least. But as a general rule, it’s pretty safe.

Unfortunately, most Australians (especially kids) are not following this advice.

In fact, recent studies have shown that the average Australian gets 60 percent of their caloriesnot just from processed food, but from “ultra-processed foods”—which consist of sugar, salt, fats, and oils plus artificial and natural ﬂavors, colors, sweeteners, emulsiﬁers, and other additives.

One of the many reasons this is problematic is because of excess sugar intake. And this was highlighted in a recent study indicating that most parents significantly underestimate their kids’ sugar intake—primarily because of hidden sugar in processed foods that are commonly seen as “healthy.”

For example, over 90 percent of parents underestimated the amount of sugar in yogurt, by an average of seven cubes, or about 60 percent of the total amount of sugar per serving.

Perhaps not surprisingly, the misjudgments were closely correlated with the children’s body mass index (BMI). In other words, the parents with the largest underestimates of sugar content in foods had kids with the highest BMIs.

The simplest way to avoid this problem is to “just eat real food.” This means cutting out the highly processed and refined foods that have become a mainstay of the Australian diet and focusing on fresh, nutrient-dense, whole foods.

Yes, it can be a difficult transition—especially if your kids are used to eating junk.

But that’s not a reason not to do it. Many parents have gone before you, and there are plenty of resources out there now to make it easier.

With almost 20 percent of kids now obese, we urgently need to bring more attention to how they are eating. And reducing sugar consumption is probably the most important first step.